There are communication systems which comprise both wired and wireless access network. Such a communication system typically comprises at least one server and a number of clients. The clients can communicate with the server and other clients through different parts of the network. The wireless access network has one or more access point devices. The wireless clients can have access to the wireless access network through the access point devices. On current wireless access networks access point devices typically operate as link layer bridges between a wired access network such as Ethernet and the wireless access network such as WLAN. The wired access network and the wireless access network usually belong to a single IP sub-network. Every device (client, server, access point, etc.) connected to the network must have a unique IP address which is used when the device sends packets to the network and when unicast or multicast packets are sent via the network to the device. Normally such an IP sub-network has an address range in which addresses of all the devices of the sub-network belong.
Situations may exist in which transmission of information should be restricted only to the wired access network or to the wireless access network of the communication system. For example, the transmitting device is not aware of if the transmission in the wireless access network is encrypted or not. Consequently, transmission of any confidential information to the wireless access network should be prevented to avoid eavesdropping of the information. However, in current communication systems it is not possible to automatically distinguish which devices are connected to the wired access network and which devices are connected to the wireless access network of the IP sub-network. Therefore the configuration of the devices has to be performed manually. This means that the access points of the communication system have to be pre-configured with the IP addresses or address ranges of the wired nodes and/or the wireless nodes of the communication system.
There may also be situations in which direct transmission from a wireless client to another wireless client should be prevented. This means that the access point through which the transmitting wireless client communicates with the network should have the information whether the receiving client is connected to the wireless access network or to the wired access network. In prior art systems, the only way to inform the access point is manual configuration, which is time consuming and every time a new client is inserted to or removed from the communication system the configuration has to be performed again.